MAX14859

The MAX14857/MAX14859 isolated RS-485/RS-422 transceivers provide 5000V_RMS (60s) of galvanic isolation between the cable-side (RS-485/RS-422 driver/receiver-side) and the UART-side of the device. Isolation improves communication by breaking ground loops and reduces noise when there are large differences in ground potential between ports. These devices allow for robust communication up to 500kbps (MAX14857) or 25Mbps (MAX14859).

The devices include an integrated 450kHz transformer driver for power transfer to the cable-side of the transceiver using an external transformer. An integrated LDO provides a simple and space-efficient architecture for providing power to the cable-side of the IC.

The devices include one drive channel and one receive channel. The receiver is ¼-unit load, allowing up to 128 transceivers on a common bus.

Integrated true fail-safe circuitry ensures a logic-high on the receiver output when inputs are shorted or open. Undervoltage lockout disables the driver when cable-side or UART-side power supplies are below functional levels.

The driver outputs and receiver inputs are protected from ±35kV electrostatic discharge (ESD) to GNDB on the cable-side, as specified by the Human Body Model (HBM).

The MAX14857/MAX14859 are available in a wide body 16-pin SOIC package and operate over the -40°C to +105°C temperature range.

Applications

• HVAC
• Industrial Automation Equipment
• Power Meters
• Programmable Logic Controllers